Engine



Oct. 4, 1955 L. E. CLARK 2,719,516

ENGINE Filed July 6, 1953 2 Sheets-Sheet l l N VHN 'I )1 LawrenceEdward Clark,

ATTO RNEYS L. E. CLARK Oct. 4, 1955 ENGINE 2 Sheets-Sheet 2 Filed July 6, 1955 JNVENTOR. 7 Edward Clark,

Lawrence AITDRNEYS United States Patent ENGINE Lawrence Edward Clark, Broken Bow, Nebr.

Application July 6, 1953, Serial No. 366,349

2 Claims. (Cl. 12392) This invention relates to internal combustion engines, and more specifically to prime movers of the diesel type wherein means are provided to convert the conventional diesel engine to utilize natural gas, a fuel which is normally less expensive than the fuels ordinarily consumed in such engines. In attempting to take advantage of such an inexpensive fuel considerable conversion problems have been encountered especially with respect to mechanisms designed to actuate the gas admission valve. Heretofore, it has been proposed to employ chain and gear driven systems, but these have proved to be quite complicated in construction, expensive to manufacture, and involved high maintenance costs as they were very difficult to maintain in adjustment. Hydraulic and other systems have also been proposed, but these too were found unsatisfactory for similar reasons. involved in making these prior art conversions was so high as to be impractical even if some degree of success was achieved through their adaptation.

Thus, a primary object of. this invention is to provide means for converting a conventional diesel type internal combustion engine into an engine using natural gas as its fuel.

A further object of this invention is to provide conversion means of the type referred to above which includes a cylinder head having a gas admission valve incorporated therein, and including fluid pressure means for actuating the valve.

A still further object of this invention contemplates the provision of fluid pressure actuating means for the gas admission valve which is automatic and positive in operation as a result of a functional characteristic of the engine with which the mechanism is operably associated.

Another object of this invention is to provide an actuating mechanism for the gas admission valves of a converted two-cycle diesel engine wherein the mechanism is operated under conditions of high and low pressure derived as the natural functions of the engine under normal operating conditions.

It is still a further object of this invention to provide natural gas admission valve actuating for converted twocycle diesel engines which are non-complex in construction, inexpensive to manufacture, install and to maintain.

Other and further objects and advantages of this invention will become apparent from a consideration of the following specification when read in the light of the accompanying drawing, in which:

Fig. l is a side elevation of a two-cycle, three cylinder, diesel engine converted and constructed in accordance with this invention; and

Fig. 2 is a vertical cross-sectional view taken on the plane of the line 2-2 of Fig. l, and looking in the direction of the arrows.

Figure 3 is a side elevational view of an engine similar to that shown in Figure 1, showing a modification wherein air for operating the valves is taken from the crank case with a header and fed to the valve operating cylinders with a distributing valve.

Additionally the expense 9 2,719,516 Patented Oct. 4, 1955 "ice Figure 4 is a detail showing a section through the driving instrumentalities of the distributing valve, parts being broken away and parts being shown in elevation.

Figure 5 is a detail similar to that shown in Figure 4, taken from a point at a right angle to that shown in Figure 4.

Figure 6 is a cross section through the air distributing valve, parts being broken away and parts shown in elevation.

Figure 7 is a longitudinal section through the distributing valve taken on line 7-7 of Figure 6.

Referring now more specifically to the drawing, reference numeral 1 designates, in general, a three cylinder, twocycle, diesel type internal combustion engine converted and constructed to utilize natural gas as its fuel in accordance with the teachings of this invention.

In the embodiment herein disclosed and illustrated, the engine 1 comprises a suitable base 2 adapted to house the lower crankcase ends of a plurality of identically constructed cylinder blocks 3, 3', 3", and hence, in the interest of brevity the details of their construction and associated elements will be set forth below with specific reference to cylinder block 3.

As shown in Fig. 2 of the drawing, the cylinder block 3 is bored and reamed to form an internal cylinder 4 which is adapted to receive a reciprocating piston (not shown), and is provided with a conventional water jacket 5. Kinematic means Well known in the art connects the piston with a crankshaft housed within the lower end of each cylinder block, the crankshaft terminating in an external end portion 6 on which an inertia wheel 7 is fixedly mounted for rotation therewith. While other firing sequences may be employed, for the purpose of this disclosure let it be presumed that the sequence is one-three-two.

In converting this diesel engine to utilize natural gas as its fuel, the usual and conventional cylinder heads including the fuel injection nozzles and other apparatus or elements normally associated therewith are removed and the cylinder heads 8, 8, 8" are substituted therefor. As is seen in Fig. 2, the head 8 is provided with a transverse horizontal passageway 9 which is in open communication at its inner end with a substantially centrally positioned bore 10 having a lower end portion 11 of reduced diameter to form an internal inwardly extending annular shoulder 12. The outer end of the passageway 9 is connected with a fitting 13 secured to the head 3 by bolts 14, and threaded pipe links 15 connect the fitting 13 with a connector 16 which is, in turn, connected with a source of natural gas under pressure, through the gas header pipe.17.

A vertically elongated, substantially cylindrical valve casing 18 is positioned within the bore 10 and terminates in an enlarged annular flange 19 at its upper end adapted to be supported on and to overlie adjacent portions of the head 8 whereby the downward movement of the casing 18 within the bore 10 is limited. The lower end 20 of the casing 18 is reduced in diameter to fit snugly within the lower end portion 11 of the casing and to provide an integral annular shoulder 21 which in cooperation with the shoulder 12 clamps a gasket 22 therebetween. The valve casing 18 is also formed with an external circumferential groove 23 adjacent its upper end to receive a ring gasket 24 preferably constructed of rubber.

The valve casing 18 is provided with a plurality of vertically aligned and centrally positioned bores 25, 26, 27, of decreasing diameters, with the uppermost thereof having the greatest diameter, the bores forming the circumferential shoulders 28 and 29.

As is seen in Fig. 2, the casing 13 is constructed adjacent its lower end with a substantially horizontal bore 30 extending diametrically thereacross and aligned with the inner end of the passageway 9. A substantially ver tical bore 31 extends inwardly from the lower end of the casing 18 and communicates at its inner end with the horizontal bore while its outer end is bevelled at 32 to form a valve seat for the gas admission valve 33.

The valve '33 is secured to the lower end of a valve stem 34 which is slidably mounted for reciprocation within a vertically elongated sleeve 35, the latter being disposed 'within the bore 27 and having an upper extension thereof projecting into but spaced from the Wall of 'the bore 26. A circumferential flange 36 is integrally formed with the sleeve'35 and abuts against the shoulder 27 to limit the downward movement thereof within the bore27. A second sleeve 37 is slidably mounted on the valve stem 34'adjacent its upper end and'is provided with a circumferential shoulder 38 comprising an abutment for one end of a helicoidal spring 39 having its other end in abutting relationship with the flange 36. A locknut 40 is threaded on the upper end'of the valve stem 33 and bears against the upper end of the sleeve 37 'to provide control for'the compression of the spring 39. The sleeve 37 is also constructed with anintegrally formed circumferential flange 41 which is'adapted to engage against, during downward movement of the sleeve, a travel limit ring 42positioned between gaskets 43 and 44, these latter elements being supported on the shoulder 28.

Again referring to Fig. 2 of the drawing, the upper end of the valve stem 34 is centrally bored to receive the lower end of a vertical valve stem extension member 45 which is silver soldered or otherwise fixedly secured therewith. The extension member 45 is adapted 'for reciprocation within a vertically elongated substantially hollow cylindrical support member designated, in general, by the reference numeral 47 As seen in Fig. 2, the extension member 45 is slidably mounted in a guide passage 48 which communicates at its upper and lower ends with recesses 49 and 50, respectively, centrally positioned and extending inwardly from opposed ends of the support member 47. The lower end of the support member 47 is reduced'in diameter at 43 to fit snugly within the bore 25 and the upper end thereof is also reduced 'in diameter forming a boss 49 and the shoulder 50. The boss 49 is adapted to be received within a central aperture 51 provided-in a circular base plate 52 of a substantially cylindrical piston casing indicated, in general, by the reference numeral 53, and is supported in its elevated position on the shoulder 50.

The extension member 45 extends above the base plate 52 and reciprocates within a bronze guide 54 disposed within recess 49 together with suitable packing 55. Upward displacement of the guide 54 is prevented by a substantially circular stop disk 56 in abutting relation with the upperend of the guide 54 by means of a plurality of stud bolts 57 which pass through apertures formed in the disk 56 aligned with tapped openings 58 provided-in the upper end of the support 47. The valve stemextensionmember 45 is lubricated through a horizontal passage 59 connected by a pipe 60 to a header 61 (see Fig. l) which is connected with a suitable lubricating source.

The upper end of the valve stem extension member 45 is externally threaded to receive an internally'threaded arbor 62 on which is supported a reciprocating piston 63 which is locked in place on the valve extension member 45 by the locknut 64.

The piston casing 53 includes the base plate 52, a circular side Wall 65 integrally constructed with an upper end wall 66 having a transverse threaded aperture 67 extending therethrough to afford connection with one end of an air conduit 68. The lower end of the side wall 65 is detachably received within a circumferential groove 69 formed in the base plate 52 adjacent the periphery thereof. A plurality of threaded stud bolts 70 are secured to the side wall 65 and project through transverse apertures 71 formed in the base plate 52 and receive nuts 72 to releasably secure the side wall 65 and the upper end wall 66 thereto. Additional apertures 73 extend transversely through the base plate 52 and are aligned with aplurality of bolt receiving passages 74 extending longitudinally through the flange 19 and which are, in turn, aligned with tapped openings 75 provided in the head 3. Bolts 76 pass through the apertures 73, passages 74 and are threaded in the tapped openings 75 whereby the casing 53, support member 47, and the valve casing 18 are all releasably secured to thehead 8.

An adjustable control valve 78 is disposed within the conduit 68 to control the admission of air under pressure to one side of the piston 63 and a vent'79 formed in the base plate 52. permits. air compressed on the other side thereof to be exhausted to the atmosphere. The air control valve 78 is fixedly secured to one end of a valve stem 80 threaded through a boss 81, and terminates in a manually manipulated knob 82.

As is seen in Fig. 1, the conduit 68 connects at its other end with the crankcase of the cylinder block 3", the conduit 68 connects the crankcase of cylinder block 3 with the piston casing 53', and the conduit 68" connects the crankcase of cylinder block 3 with piston 53".

In the above described and illustrated embodiment of this invention it will be presumed that Fig. 2 illustrates the position of the gas admission valve 33 and its actuatingmechanism immediately after the working piston in cylinder 4 of cylinder block 3 has passed its dead center position and is beginning its compression stroke. As the compression stroke is initiated the cylinder scavenging and exhaust ports are closed by the working piston and air isdrawn into the crankcase below the piston in cylinder 4. Substantially simultaneously therewith air which hadpreviously beendrawn into the crankcase of cylinder block 3' is being compressed and passes through conduit '68 to exert a downward pressure on the upper side'of the piston 63. The pressure is such as to overcome the force of the spring 39 whereby the piston 63, extension member '45, valve stem 34, and the valve 33 are moved downwardly to permit gas to enter the cylinder 4from the header 17.

As the working piston in crankcase 3 approaches the ignition point the working piston in crankcase 3 uncovers scavenging and exhaust ports connected therewith wherebythe pressure in conduit 68 is relieved and the force of spring 39 then returns the valve 33 and the actuating mechanism'therefor to "their respective positions as shown in Fig. 2.

As'theworking piston of crankcase 3 starts its working stroke air pressure begins to buildup in the casing 53 through conduit'68' to'operateits valve actuating mechanism, in the same manner as described above, and upon ignition of the gas admitted to'its cylinder and upon the start of its working stroke, -air begins to buildup in pressure in conduit 68" on the'valve actuating piston in casing 53".

In the designshown in Figure 3, an air distributor 100 is positioned atone end of the'engine and the air is carried to the valve through a header or tube 101, with check valves in the connections 86between the crank case and header.

The air under pressure from thecrankcase of the engine is supplied to the actuating cylinders 53 of the valves of the cylinders of the engine by a distributor which is connected'to the crankcase with a tube 1411. The tube 101 opens into an open chamber'102 from which the air passes through openings 103 in a flange .104 at one end of a rotor 105.

A flange 106 at the opposite end of the rotor is provided with an opening 87 providing an outlet airpassage whic'h'com'municates with an outlet connection 88 through an area'89. The compressed air passes through the passage 107 and through the-opening 109 of the rotor into areas 110 in the distributor housing from which the air is supplied to the cylinders 53 of the respective cylinders of the engine.

The rotor is provided with an extension =111..that.car-

ries the air to ports 112 in an annular wall 113 around the rotor whereby the air passes through chambers or areas to outlet openings 115 that are connected by tubes 116 to the valve control cylinders 53. The return or exhaust air from the cylinders is connected by similar tubes to openings in chambers 117 on the opposite side of the center of the distributor.

The rotor 105 of the distributor is mounted on a shaft 118 which is driven by bevel gears 119 and 120 from a timer 121, the gear 120 being mounted on the timer shaft 122.

The rotor is illustrated in Figure 5 with the passage 123 of the extension 111 in communication with port No. 1 of the wall 113, and traveling in a counter-clockwise direction from the position shown the passage 123 moves to the ports No. 2, No. 3, No. 4, No. 5 and No. 6.

Opening 115 represents the outlet of No. 1 port, 125 the outlet of No. 6 port, 126 the outlet of No. 2 port, 127 the inlet of No. 2 port, 128, the outlet of No. 5 port, 129 the outlet of No. 3 port and 130 the outlet of No. 4 port. Corresponding openings are provided on the opposite side of the center.

Having described one embodiment of this invention in detail, it will be understood that the same has been offered only as an example thereof, and that the invention is to be limited only by the scope of the following claims.

I claim:

1. In an internal combustion engine, the combination which comprises an engine block having cylinders with pistons therein and having a crankcase, said cylinders having intake valves therein, valve control means for said intake valves, and a distributor for, selectively, supplying compressed air from the crankcase to the valve control means of the cylinders.

2. In an internal combustion engine, the combination which comprises an engine block having cylinders with pistons therein and having a crankcase, said cylinders having intake valves therein, valve control means for said intake valves, and a distributor having a rotor with a passage therethrough for, selectively, supplying compressed air from the crankcase to the valve control means of the cylinders.

References Cited in the file of this patent UNITED STATES PATENTS 866,538 Thomas Sept. 17, 1907 885,459 Engler et a1 Apr. 21, 1908 1,383,163 Scott June 28, 1921 2,255,355 Harris Sept. 9, 1941 2,552,960 Grieshaber et al. May 15, 1951 2,667,155 Paluch et a1. Jan. 26, 1954 

